This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The GINS complex, consisting of at least four different polypeptides, plays an important but as yet undefined role in DNA replication of eukaryotes. In this work, we are using a series of biochemical techniques developed in the laboratory in conjunction with genetic manipulation of yeast to throw light on the function of this complex.